The limbic system includes structures in the cerebral hemispheres as well as diencephalic structures: A. Some limbic structures in the cerebral hemispheres are the amygdala, the cingulate gyrus, septal nuclei, hippocampus dentate gyrus, and the parahippocampal gyrus. B. Some of the diencephalic limbic structures are the hypothalamus, and the anterior thalamic nuclei. Several fiber tracts connect the various components of the limbic system. Some of these tracts are the fornix, the stria terminalis, and the medial forebrain bundle.
Work Step by Step
The limbic system comprises several groups of structures located in differen parts of thebrain, these structural components are united by groups of input and out put fibers that enable the limbic system to function as a coordinated entity Structural Elements in the cerebral hemispheres: Amydaloid body, cingulate gyrus, septal nuclei dentate gyrus, hippocampus, , parahipocampal gyrus, a accumbens nucleus", orbital cortex, insular cortex, Structural elements in the diencephalon; Hypothalamus, anterior thalamic nuclei Fiber Tracts Fiber tracts connect the widely separated elements of the limbic system and facilitate communication and coordination. The main fiber tracts are fornix, the stria terminalis, the medial forebrain bundle and the mammilothalamic tracts. The main input structures of the limbic system are the amygdala and the hypothalamus out is mainly through activities of the septal nuclei and the hypothalamus The amygdala responds to threats by showing anger or fearful expressions. The cingulate gyrus is concerned with expressions of grief and mental frustration. The hypothalamus deals with emotional responses as well as autonomic visceral reactions . Because the hypothalamus is a center that deals with these two types of activities, emotional stress can cause visceral effects such as changes in heart rate, blood pressure, and respiratory rate. These are the so-called psychosomatic responses or effects, Because of its cortical connections the the limbic system (feeling brain) can also be affected by the thinking part of the brain. Consequently, our emotions can be affected by logic, and reason can control expressions of emotions.